Arresting hook retracting mechanism



',Oct; 7, 1947. `D. s. SANBORN Er AL.

ARRESTING HOOK RETRACTING MECHANISM 2 Sheets-Sheet l Filed March 28, 1945 AT TORNEY D. s. sANBoRN ET AL 2,428,684

ARRESTING HOOK RETRACTING MECHANISM Oct. 7, 1947.

Filed Maron 28, 1945 2 sheets-sheet 2 INVENTR. Damet S Sanborn' BY Earl A. Kops ATTO'LISIY Patented Oct. 7, 1947 ARRESTING HOOK RETRACTING MECHANISM Daniel S. Sanborn and E arl A. Kops, San Diego,

Calif., assgnors to The Ryan Aeronautical Co.,

San Diego,

Application March 28,

10 Claims.

Our invention relates to an arresting gear operating means for use in connection with carrier based airplanes, for arresting an airplane when landing and for stowing the arresting hook in the airplane.

In order to maintain the most eiicient aerodynamic character of the airplane, it is desirable to retract the arresting gear and stow the same inwardly of the skin surface of the fuselage, especially in the case when the airplane is equipped with tricycle landing gear. The position of the arresting gear when used with tricycle landing gear is considerably forward of the tail of the airplane and terrupts the slip stream if left protruding from the fuselage of the airplane. In the design of high speed airplanes such aerodynamic considerations are very critical.

As the landing operation of carrier based airplanes is dependent on the engagement of the arresting hook of the airplane with the cable on the landing deck, it is desirable to prevent bouncing of the hook on the landing deck. I

In order to be reliable, the hook must travel in close engagement with the landing deck so that it does not jump the arresting cable. Such operation of the hook is accomplished by the provision of hydraulic dampening means, which resists the bouncing tendency of the hook as it contacts the landing deck.

In the drawings accompanying tion,

Fig. 1 is a side elevational view of the mechanical structure of our arresting gear operating means, showing stationary structurer of the airplane by dash lines and also showing the stowage of the arresting hook by dash lines.

Fig. 2 is an end View taken of the structure as shown in Fig. 1.

Fig. 3 is a dash line view of an airplane showing our arresting gear operating means in connection therewith.

Fig. 4 is a diagrammatic View of the hydraulic equipment of our arresting gear operating means, showing the retraction of the cylinder plunger.

Fig. 5 is a similar view to Fig. 4, showing the extension of the cylinder plunger; and Fig. 6 is another similar view to Fig, 4, showing the bleeder valve in operative position, whereby dampening of the cylinder plunger is effected.

Similar characters of reference refer to similar parts and portions throughout the several views of the drawings.

The arresting hook 5 is a conventional hook member adapted to engage the arresting cable on aircraft carrier decks, not shown, and is provided this specica- Calif., a corporation of California 1945, serial No. 535,278

with a shank 6, which is pivoted laterally of the aircraft axis on the bolt 1, which is mounted in the bellcrank member 8. This bellcrank member 8 is pivoted on the bolt 9, which is near the upper end of the hook member 5,V and the bolt 9 forms the pivotal axis of the hook member 5. The bell crank member 8 is connected by a bolt II to the plunger shaft I2 of the hydraulic cylinder I3. The hydraulic cylinder I3 is stationarily pivoted to the structure of the airplane by the bolt I4. The track member I5 is stationarily pivoted to structure of the airplane by the bolt I6, and is provided with Slotted track portions I1, in which' the bolt 9 is slidably mounted. The link member I8 is stationarily pivoted on the bolt I9, in connection with structure of the airplane. The

opposite ends of the link I8 are positioned onv the bolt 9, and guide the bolt 9 in an arcuate path as it slides in the slotted track portions I1.

Communicatingwith the hydraulic cylinder I3 through the tube 30, is a bypass valve 2 I, in which is slidably positioned the piston '22. A spring 23 in the bypass valve 2I tends to hold the piston 22 in the position as shown in Fig, 6. Communicating with the bypass valve 2I is a suction tube branch 24 which is shut the position as shown in Fig. 4.

Communicating with the bypass valve 2l is al pressure tube 25. Within the bypass valve 2I is a passage 26 which communicates with opposite ends oi the piston 22 when in the position as shown in Fig. Li.

Communicating with the three-way valve 21 which either interconnects the pump 23 and the pressure tube 25 or the pressure tube 25 and the reservoir 29.

The suction tube 3| intercommunicates the reservoir 29 and the 'bleeder valve 32. The bleeder valve 32 communicates with the opposite end of the hydraulic cylinder I3 from the extended plunger l2 and tends to dampen the action of the plunger when traveling inwardly into the hydraulic'cylinder I3. The bleeder valve 32 is provided with a slidably mounted bleeder piston 33, having a seat 34' which when closed limits the passage of liquid to the orifice-35. When this valve seat 34 is open as shown in Fig. 5, liquid passes in volume through notches in the periphery of the piston 33. The spring 35 tends to hold the seat 34 closed. The spring 36 is compressed bythe force of liquid entering from the reservoir oi by the piston 22 iny vthe pressure tube 25 is permittingthe spring The operation of the arresting hook operating means is substantially as follows:

When landing, the airplane to which the arresting gear operating means is attached, the valve 21 is turned to the position as shown in Fig. 5, relieving the pressure on the piston 22 and 23 to force the piston 22 away from the suction tube branch 24. The springs 37 and 38 force the plunger l2 from the cylinder I3, causing suction on the bleeder valve 32 anddrawing liquid from plunger piston through the tube 30, bypass valve 2 l, and the suction tube branch 2li.V

As the hook contacts the landingdeck, ithafs' a tendency to bounce, but is dampened bythe restriction of the liquid passingthrough the orifice 35 of the bleeder the other sideof the Vvatir'ig and stowing said hook member in the airmoves along the track, and actuating means ai*-Y ranged to pivot said hook member and move the Y plane, said hook member pivotal laterally of the thereby maintained and held closely to the landing deck by the springs 31 and 38.

When retractingthe hook 5, the valve 21 is turned yto the drawing,

to the bypass valve 2|. The piston 22 is forced against the spring"23, compressing the same and closing the suction tube branch 2 4. Hydraulic pressure is conducted by thepassage ZBto the tube 3l)` and against the `piston 39 on the plunger shaft.|2. Liquid passes from the opposite side of theV piston 39 through the bleeder valve 32. As the plunger l2. retracts into the hydraulic c'yl-v inder i 3, the bolt llslides inthe slotted track portions l1 to the end'thereof, causes the bolt S'to travelv in an .arcuate path about the axis furnished'by the'bolt I9, thereby raising the pivotal axis: of the hook member 5. When the bolt'v 9 has reached the'en'd ofthe slotted track portions I1, the bell crank member 8 is pivoted on'the bolt 9 and the hook member 5 is pivoted and stowed inthe airplane as shown by dash lines in Fig. 1 of rthe drawings.

Having' thus described our; invention, what we claim as new and desire to' secure by Letters'Patient isf i 1. In an arresting'ho'k operating gear for air-r planes, a track member pivotally connected' to the airplane,a hook memb'erpivotally slidable inthe track member-,and means for elevating the hook member and stowingthejsame within the airplane substantially parallel' t'othe longitudinal axis thereof.`

`2. In an arresting hook operating gear for 'aire' planes,` a track pivotally connected to an airplaneY and extending downwardly below the fuselage of the airplane, a hook member pivotally slidableV in the track, and means' :forV elevating said track andhook member for stowing the same wholly within the fuselage of said airplane.

3. In an arrestirighook operating gear for airplanes, a hook member having a hook portion on one end and pivotally connected to an airplane near its other enclin` track supporting saidV hook member whereby said hook member near its said other end is movable along said track, means for elevating said track and actuating means for elevating and stowing said hook member in the airplane.

4; In'an arresting hook operating gear for airi planes, a hook member having a hook portion on one end, a track pivotally connected'to an airi plane and supporting said hook member near its other end, whereby said hook member is movable along the track,va lin k stationarily'pivoted at one end to the airplane and arranged to elevateV the track at Vits other end'when said hook member positionY as shownk in Fig. 4of thef whereby hydraulic pressure is conveyed from the pump 28v through ,the pressure tube 25V while the link |8- axis of said airplane.

6. Inaniarr'esting hook operating gear, a hook 1`5 member. havingafliook portion on one end and valve 32.. The hook 5" is pivotallycorinected near its other end to an airplane," a link Ys'tationarily pivoted on said airplane at. one end and pivotally connected on a common axis with said hook membery at its other end, and a track pivotally connected to said airplane and supportingg said yhook membenwhereby the'` axis oflsaid hook member is-'movabief aiongl the ftiack, Ypivotal movement of saidiinkfand wherebythe elevates said trac ber.

7. In an arresting hook operatingl gea-na hook member having a'hook" portionon onefendand pivotally connected near itsV other end to an airtogether with said hook'Y mem# and a track pivotally connected tosaid airplane and supporting said hook member, whereby the' axis of said hook member is movableA along the track, and whereby the pivotal movement of said link elevates said trackv together with saidhopk member, a hydraulic cylinder in connection with said hook member arranged-to pivot Athe hook member andV stow the same in the airplane.

8. In anarr'esting gear for airplanes, a hookj member having ahookv portion on its extended end and extendable below the fuselage of an'airplane, an hydraulic cylinder provided with a plunger connected to said hook member, a spring i'n said cylinder arrangedrto extendthe hook member, a suction tubecommunicating withone end of the cylinder, a pressure conductor com-v municating with the other end` of thejcylinden a bypass valve having .inletand outlet passages interconnecting said suctionVV tube and said'Y pres- Vsure conductor, wherebyv iiuid expelled through said pressure conductor from said'cylinderis is@ sued into saidY suction tube, and whereby fluid passing throughs-said pressure conductor to said cylinder bypasses the valve :communicating with vthe inlet side of said 'by-pass valve, anda reservoir communicating .with said three-way valve and said suction tube.

9. In an arresting hookloperatingV` gear for fairplanes, a'hook member having a hook portion on one end and pivotally connected to an airplane near its other end,` a track supportingsaidhook member whereby said hookV memberV near itsfsaid other end is rmovablealong saidtr'ack, means `'for elevating said track andactuatng means for elevating and stowingsaidhook plane, a bell crank member" i mount for said hook member whereby the hook member ispivotally mounted llaterally offsa'id Y near itstherfend, altrack supporting said ,hookl suction tube, aY three-way l member in'theairi providing `the pivotal s inember whereby said hook member near its Said other end is movable along said track, means for elevating said track and actuating means for elevating and stowing said hook member in the airplane, a bell crank member providing the pivotal mount for said hook member whereby the hook member is pivotally mounted laterally of said airplane on said bell crank member, and is pivotal vertically with said bell crank member, said bell crank member provided with an extending arm portion connected With said actuating means.

DANIEL S. SANBORN.

EARL A. KOPS.

REFERENCES CITED The following references are of record in the le of this patent:

Number Number 6 NT STATES PATEN""""'S Name Date Hall Nov. 24, 1925 Minshall Mar. 4, .1930 Levy Feb. 14, 1939 Dunn July 17, 1934 Clarke Oct. 11, 1938 Levy May .14, 1935 FOREIGN PATENTS l Country Date Great Britain Mar. 30, 1933 Italy Mar. 11, 1937 

